{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,2,20]],"date-time":"2026-02-20T08:38:36Z","timestamp":1771576716109,"version":"3.50.1"},"reference-count":33,"publisher":"MDPI AG","issue":"2","license":[{"start":{"date-parts":[[2021,1,31]],"date-time":"2021-01-31T00:00:00Z","timestamp":1612051200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Symmetry"],"abstract":"<jats:p>This article is dedicated to establishing a novel approach to the cosmological constant, in which it is treated as an eigenvalue of a certain Sturm\u2013Liouville problem. The key to this approach lies in the proper formulation of physically relevant boundary conditions. Our suggestion in this regard is to utilize the \u201cholographic boundary condition\u201d, under which the cosmological horizon can only bear a natural (i.e., non-fractional) number of bits of information. Under this framework, we study the general d-dimensional problem and derive the general formula for the discrete spectrum of a positive energy density of vacuum. For the particular case of two dimensions, the resultant problem can be analytically solved in the degenerate hypergeometric functions, so it is possible to define explicitly a self-action potential, which determines the fields of matter in the model. We conclude the article by taking a look at the d-dimensional model of a fractal horizon, where the Bekenstein\u2019s formula for the entropy gets replaced by the Barrow entropy. This gives us a chance to discuss a recently realized problem of possible existence of naked singularities in the D\u22603 models.<\/jats:p>","DOI":"10.3390\/sym13020237","type":"journal-article","created":{"date-parts":[[2021,1,31]],"date-time":"2021-01-31T04:53:00Z","timestamp":1612068780000},"page":"237","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":2,"title":["The d-Dimensional Cosmological Constant and the Holographic Horizons"],"prefix":"10.3390","volume":"13","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-9564-0312","authenticated-orcid":false,"given":"Artyom V.","family":"Yurov","sequence":"first","affiliation":[{"name":"Department of Physics, Mathematics and Informational Technology, Immanuel Kant Baltic Federal University, Al.Nevsky St. 14, 236041 Kaliningrad, Russia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9854-8960","authenticated-orcid":false,"given":"Valerian A.","family":"Yurov","sequence":"additional","affiliation":[{"name":"Department of Physics, Mathematics and Informational Technology, Immanuel Kant Baltic Federal University, Al.Nevsky St. 14, 236041 Kaliningrad, Russia"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2021,1,31]]},"reference":[{"key":"ref_1","unstructured":"Barrow, J.D., and Tipler, F. 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